This invention relates to finishing operations involving hot-dip zinc spelter coating strip steel. In its more specific aspects this invention is concerned with minimizing aqueous requirements for caustic cleansing solution supply purposes; and, with substantially-eliminating aqueous waste discharge from surface-cleansing operations.
An important object is to provide for continuing uniform surface cleansing by maintaining uniform purity-level standards for the cleansing solution.
Another object is to enable minimizing of waste disposal, in particular, substantially-eliminating contaminated waste water disposal.